1. Field of the Invention
This invention relates to the finding of stress-induced phosphoprotein 1 (STIP1) as a biomarker for the detection of human ovarian cancers and endometriosis. Based on said finding, this invention provides a method for the detection, preliminary screening or monitoring of a gynecological disease selected form ovarian cancers and endometriosis, in which STIP1 is used as a biomarker for the gynecological disease.
2. Description of the Related Art
Ovarian cancer is the leading cause of gynecological cancer death. The high case-fatality rate of ovarian cancer is mainly attributed to the fact that most ovarian cancers are diagnosed in advanced stages, III or IV, where the cancer has spread beyond the pelvis. On the contrary, stage I ovarian cancer that is limited to the ovaries has a survival rate of over 90 percent. Early detection of ovarian cancer appears to be the best strategy for reducing ovarian cancer mortality.
The majority (90%) of ovarian cancer is epithelial origin, including the serous type (70%), mucinous (10%), and endometrioid (10%). The remaining 10% originates from germ cell or stromal sex cord. Measurement of serum levels of a glycoprotein, CA125, has become standard practice for the preoperative evaluation of ovarian masses (Ben Van Calster et al. (2007), J. Natl. Cancer Inst., 99(22):1706-1714). However, the overall sensitivity of detecting ovarian cancer is about 80%, with the highest in serous type (94%) and the lowest in granulose cell tumor (30%)(David M. Robertson et al. (2007), Cancer Letters, 249 (1):14-17). Therefore, more tumor markers for detecting and monitoring ovarian cancer are highly desired.
For example, inhibin has been investigated for use as a diagnostic marker for ovarian cencer (David M. Robertson et al. (2007), supra).
WO 99/57565 discloses methods for cancer diagnosis, and more particularly to the use of compounds that detect expression of OB-cadherin or N-cadherin for diagnosing and determining the metastatic potential of cancers such as breast, ovarian and prostate cancer, as well as leukemia.
U.S. Pat. No. 7,189,507 B2 discloses genes whose expression is up-regulated or down-regulated in ovarian cancer. Referring to Table 14A of the Specification of U.S. Pat. No. 7,189,507 B2, there is listed a gene that is identified to correspond to the gene deposited with Accession No. AF129085, which is Homo sapiens carboxy terminus of Hsp70-interacting protein (CHIP)[also known as STIP1 homology and U-box containing protein 1 (STUB1)] mRNA.
U.S. 2004/0096915 A1 discloses a method for the diagnosis, prognosis, and monitoring of ovarian cancer in a subject by detecting human kallikrein 6 (hK6) in a sample from the subject, preferably a serum sample or tumor tissue extract.
Despite of the aforesaid, many investigators endeavored to explore new biomarkers for ovarian cancers. The applicants surprisingly found form experiments that the levels of STIP1 in patients with ovarian cancers and endometriosis were significantly higher than those in normal controls, suggesting that STIP1 be useful as a biomarker for the detection of ovarian cancers and endometriosis.